


Haruspex Traitor Innocent

by tealmoon



Category: Undertale (Video Game)
Genre: Alternate Universe - Underfell (Undertale), Child Death, Corpse Eating, Divination, Fellcest - Freeform, Gore, Implied Sexual Content, M/M, Mutilation, Non-Consensual Drug Use, pretty sure this is not what religion kink is
Language: English
Status: Completed
Published: 2018-12-07
Updated: 2018-12-07
Packaged: 2019-09-13 09:05:21
Rating: Mature
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 1
Words: 2,278
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16889631
Author URL: https://archiveofourown.org/users/tealmoon/pseuds/tealmoon
Summary: A human falls into the Underground. And dies. And becomes part of something far bigger. Sans is willing to get his hands dirty to help his brother get the human souls he needs to ascend.





	Haruspex Traitor Innocent

There’s another human child in the Underground, and _man_ , are they fucking up.

The monster children know better. They see things adults don’t. They’re learning when to hide, and good for them, he can appreciate that sort of thing. They’ve earned their extra time alive.

This kid doesn’t know shit, though. Sure, they’re armed with a sizable kitchen knife and all the warnings the old lady must have crammed into their head. She won’t talk to him anymore, after he tried to claw open the stone door. He can smell the candle wax and the herbs and all the other wretched nasty shit that keeps his teleports from working inside the ruins. You’d think she’d keep the kids in there, where it’s slightly less dangerous.

But an exhausted kid can slip up, and when he’s had a dozen opportunities to strike and doesn’t take them, they get careless. He tosses a few bones at monsters attempting to snatch the kid away, “sneaks” them past Boss as he’s patrolling, and all of the sudden he’s not a boogieman anymore, just Sans. He hands them a little bit of money to take up to the counter at Grillby’s and stares the flame down until he brings them a complimentary milkshake to go with the fries; he plucks out Echo Flowers for them to wear in their curls, after he’s hummed out all the threats and screams and sounds of brawls.

He can’t really blame them for being taken in by his efforts. If someone had swooped into his life like that when he was a tiny kid, he would’ve been just as starry-eyed and obedient. He can see the thoughts running in their head, can imagine the sound of _Uncle Sans_ and isn’t surprised when he’s soon got a tiny squishy hand sweating in his. With his protection, they make it into Hotland with barely a few scrapes, and it’s almost precious how easy they’re making it for him.

“Hey, Muffet. Gotta customer for you.” The kid presses close to his side when he leads them into her territory, but his gold is good, which is the main thing she cares about. He has the feeling she knows his gig. She might take a fistful of coins and hand over a pair of donuts, but she’s always careful never to touch him, and there’s been spiders watching his movements since he stepped over the threshold from Waterfall. If it’s ever her turn, he’ll have to be a lot more careful.

He knows Muffet’s prices better than most, and a pair of donuts normally costs half of what he hands her. She doesn’t _like_ it, mouth pinched, but she still gives him the donuts carefully packaged in tissue paper. The world’s worst secret menu: double the price to have them drugged, triple for poisoned. She can glare all she wants over him handing them to a kid, but half the blame falls on her shoulders.

And, because he’s a nice guy, he lets the kid have both. They sit in a Hotland alcove a few minutes away and he waits for them to finish up, licking frosting off their hands. He’s pretty sure she slathers on extra icing either to mask the taste of the drug or as a pity gesture, and it’s gotten everywhere, a smear on their cheek and more on their striped shirt. In ten minutes, they’re lolling against his shoulder, dazed but still conscious. In fifteen, all their words come out slurred. They’re ready, and about time—he doesn’t spend much time in Hotland if he can help it. They’re both soggy with sweat.

“Think we’re done here,” Sans says, a hand on their shoulder, tugging them forward and back into Snowdin. They mumble something, probably asking why they’re going backward when he promised to take them all the way to the end.

He wasn’t lying, technically.

Their steps are unsteady, but with Sans’s arm around them, they stay upright. Monsters around here are lenient, but him dragging around an unconscious kid would probably set off a few alarm bells. Through all this, the kid still trusts him, maybe thinking that they’re loopy from the heat they just left behind. They obediently follow him to the shed beside his house. He holds onto them more tightly as he unlocks it and pushes them across the threshold.

The shed is a chapel now, through Papyrus’s will and Sans’s efforts. It’s too bad—the kid’s so dazed that they probably can’t admire the paintings he’s done over the walls in dust-mixed paints. It’s mostly landscapes he’s mimicked from human books, forests and fields that help them remember _why_ they’re continuing on in this shitty, dusty world. He even reversed gravity on himself for hours so he could paint the ceiling into a sky, complete with wobbly clouds. It looks holier than any human church he’s ever seen in water-stained photos. In a perfect world, they’d have stained glass windows too, snow shining through them, but fuck if he knows how those are made, and they can’t have Snowdin monsters snooping.

On the far wall is his crowning masterpiece: a portrait of the Boss himself, life-sized, a halo extending out from around his skull and echo flowers around his ankles. His arms are spread wide like he’s ready to gather monsterkind up and lead them into the future. Sans can’t remember how many sketches it had taken to make it perfect, but he doesn’t regret the effort, for once. And underneath it, there’s an abandoned throne that once belonged to the queen and now carries someone more worthy.

Papyrus is already there, waiting for them.

His betrayal is finally obvious to the kid, who tries to shove past Sans with barely any strength, who can’t pull their bruising arm from his grip, who opens their mouth like they’re going to scream but only whimpers as he throws them down onto the floor and Papyrus steps down from his elevated throne.

Their sound cuts off as Papyrus neatly breaks their neck. He’s a good guy like that, merciful; he could have left them aware for all this. A trembling soul flutters out, bright green in the dim, and Sans easily snatches it—Alphys makes special containment jars for souls, and these days, it’s easy to intimidate her into handing them over. The soul is for last; there’s a lot more to play with first. A human body lingers, so they can take his time with what’s left. Sans sits back as his beautiful, holy brother tears their striped shirt and dips his head. They open easily.

Divining with a human body is a lot different, and probably harder with what little practice Papyrus gets. With monsters, you can lean down to the dust pile, exhale, and figure shit out from the way it settles on the ground. But with humans, you gotta get through a lot of meat to find the important, future-telling parts. One wrong bite, and Papyrus could accidentally wipe out a bit of their destiny.

He didn’t mess up, of course. He never would. _Sans,_ on the other hand, could probably fuck up on that, so when Boss waves a hand, in a _yes yes go ahead you don’t need permission_ way, he aims his teeth for the throat. Nothing mystical up that high, and he gets a kick out of the idea that he’s eating the kid’s voice. Gotta be a smooth talker to get this far; might as well take any advantage he can get.

With rations tightening around their necks, it’s nice to feel full for once.

He’s still chewing when Papyrus sits back on his heels, bloody from his nasal aperture to his third cervical vertebra, bared by his similarly stained uniform. The human is ready, and he presses his hands in, spreading the gap he’s eaten away.

Sans stays silent, both out of anticipation and the need to not be a distraction. They only use humans for big fortunes: a death, a birth, a new ally, the Barrier blowing the fuck up and impaling Asgore on its shards like it was a broken glass door. Can’t waste a human body on small stuff, weather report shit, not like the monsters he used to bring Boss to practice on. He didn’t need it anymore, and all dust fortunes seemed to come out as blizzards anyway. They’re both tired of the snow.

Guts have always been Papyrus’s thing, so no amount of explanation or demonstration could help Sans find meaning out of a pile of meat. Dice rolls and playing cards are more his thing, and that seems right—all the low, common fortune telling for Sans, everything fancy and advanced for Papyrus. Less pressure on him, honestly.

“Asgore has collected four souls already but has not partaken in any,” Papyrus murmurs, and Sans wonders if it’s as easy as counting discolored spots on the large intestine, something like that. Learning the number of souls now, rather than potentially getting dusted searching for them, is well worth the price of a human body. He might be a pathetic shadow of a monarch, but Asgore has kept his security tighter than his welded-shut asshole. Maybe, just maybe, a monster with two extra human souls could take down a coward King. He always assumed Asgore would snack on at least one of those souls, but if they’re all lying around unused...

But Papyrus doesn’t stop with that. “There will be a seventh soul, stronger than the others. The last one to fall.” He has no idea how Papyrus can tell that from viscera, but he’s rapt, can’t look away. “By the time they reach us, they’ll be anointed in dust, and their strength added with mine...” He doesn’t need to say anymore than that—Sans is already imagining it. They can kill the King, take the rest, and break the Barrier.

Seven souls, and they’ll be able to see the sun. Seven souls and Papyrus’ll be able to _eat_ the sun, if he fucking wants to.

“Our futures are growing brighter by the minute,” Papyrus says, raising his elegant hands to lick the blood off, and Sans really can’t be blamed for how that gesture goes straight to his crotch. He rushes to get the kid all wrapped up in a shroud, a clean package to be dealt with later. It’s cold enough in the shed that they’ll keep for a while.

Body disposal is his job—he hacks them up for the freezer, buries the unusable parts or all of them if they’ve gone smelly, or scatters dust in places no one will notice. He sews the shrouds himself. He should be all slow and reverent with this part, but it’s hard to focus as Papyrus reaches out for the soul jar. Even in the dim, he can see smears of blood in between Papyrus’s finger joints, a little left behind on the glass as he lifts the soul out. He holds the little soul for a moment and then _bites_.

This is the second soul he’s consumed so far. There have been other bodies, but they had gotten to them too late, the soul either stolen away for the king or dissolved into the snow. They need more, Sans knows that; hopefully he can get his brother a full rainbow of souls.

But for right now, two souls is enough to make him fucking radiant. He hasn’t been scarred in months; attacks that would fracture bone now barely bruise it. His grip is stronger, and even though he’s always careful with his brother, Sans can jerk off to the idea that Papyrus could crush him into powder without effort.

That isn’t the only effect of the soul. As the last of the green shimmer fades from the air, Sans can hear bones cracking and shifting, so he crawls up into his brother’s arms and presses their mouths together. Might as well help distract him, right? Sans is still a sloppy mess of blood and sets to dirtying him up. Papyrus had made a cursory effort to lick his teeth clean of his sacrificial meal, but he fixes that in seconds.

Papyrus’s mouth soon locks in a grimace, and Sans moves his attention down to his neck, biting and licking. Mostly biting, trying to give him a better pain to focus on than what’s happening to his spine.

It doesn’t look like much, once the protrusions tear past his shirt. Like an awkward pair of extra arm bones jutting out behind him. As he gasps for breath and Sans slides his claws through the front of his shirt—it’s already torn, why not go the whole way—the new bones twitch and shiver. It’s easy to imagine what they could be, with a few more souls in him and maybe some magic for feathers. He doesn’t know what kind of bird he’s emulating, or if there’s any difference in bone structure between a dove and a hawk, but Papyrus is on his way to wings. Like the Angel he’s always been.

He’s gonna need to update that mural, he thinks, but the thought doesn’t last long as Papyrus pushes him down onto his back and climbs on top of him. He’d rather not be pinned down, hoping for a chance to touch those new partial-wings and see if they’re sensitive or not, but Papyrus is the Boss for a reason. If he wants to grind Sans into the shed floor, wrists pinned so carefully, then that’s what they’re doing. And can he really complain if he’s getting holy dick? He’s right where he wants to be.

**Author's Note:**

> Fuck December and writer's block and tumblr catching on fire, have some regrettable underfell. o((*^▽^*))o 
> 
> Swear to fuck, I was trying to do religion kink, but I feel like this proves I have no idea what that actually is.


End file.
